Improvement in saw-mills



To all whom it may concern:

ditched States @anni attire.

FRED. T. STEVENS, OF COLUMBIA, NEW HAMPSHIRE.

Letters Patent No. 108,201, dated October 11, 1870.

IMPROVEMENT IN SW-MILLS.

The Schedule referred to in these Letters Patent and making part of the same.

Be it known that I, FRED. T. STEVENS, .of Columbia, -n the county of (loos and State of New Hampshire, have invented a new and improved Sawing-Ha? chine; and I do hereby dec-lare that the following is afull, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing forming part of this specification, in which- Figure l represents a plan or top view of my improved sawing-machiue.

Figure 2 is a longitudinal vertical section of the same, taken on the plane of the line x a', tig. 1.

Figure 3 is a vertical transverse section ofthe same, taken on the plane of the line g/ y, fig. 1.

Figure 4 is a detail side view of the incline,&c., for setting the head-block.

Similar letters of reference indicate corresponding parts.

This invention relates to a new mechanism for reversing the motion ofa saw-mill carriage, and for adjusting the log on the head-block, so that the saw can be made to out during both movements of the carriage, or only during the forward motion'of the same.

The invention is more particularly applicable to elapboard-machines, and can be readily adjusted for cutting boards of any snit-able thickness.

A in the drawing represent-s the main frame of the saw-mill.

B is the saw-frame.

D ,-thc vertically-adjustable saw-sash, carrying the mandrel E, on which the saw I is mounted.

The saw-sash is provided with a rack, o, which meshes into-the teeth ofa pinion, I). The latter is mounted upon a horizontal shaft, .,c, that is, by means of bevelgear wheels d, connected with a vertical shaft, c.

The shaft c has a hand-wheel or crank, by turning which the saw can be lset higher or lower, asV may be desired.

The shaft c receives motion from suitable mechanism, and transmits it by a belt, f, to another horizontal shalt, G, which serves to regulate thc motion of the log-carriage H.

One end ofthe shaft G is hung in an ear, y, of the frame A, while the other end is hung in a slotted plate,

l1, which is arranged to slide on a har of the said frame.A

A belt, i, connects the shaft- G with the shaft I, which carries a pinion,j, for imparting motion to the carriage H, meshing into a rack on the same.

A belt, 7.', extends from the shaft I to a pulley on :mother transverse shaft, J, which is hung in the frame A, near to the shaft G.

The belt f is, during all positions 'of the shaft G or saw-sash, properly stretched by a swinging frame, l. Y

The slide 7i. is connected with a lever, L, which has one end pivoted to the frame A, while its free end rests on a longitudinal bar ofthe same frame, being drawn down upon the same by a weight, m, which is, by means of a cord, n, suspended from said lever.

The cord n passes through a hole in the end of a longitudinally-adjustable bar, M, which is supported by the frame A, and has a projecting pin, O, that is exposed to the action of pinsfp q, or equivalent projeetious from the log-carriage.

Theslide-bar M has two projecting wedges, r and s, between which the lever L rests on it.

Vhen the lever Lis in the position shown in iig 1,

vi. e., with its free end drawn by the weight into a notch, n, it draws the slide h, so as to hold frictionpulleys n' on the shafts G J together, while the belt 1'. will be slack. The carriage is then moved forward until the pin q, striking'o, will move the slide-bar M forward with the carriage. As soon as the wedge s on thc bar M is pushed under the lever L, it lifts the same out ofthe notch u, and releases it, so that the weight can pull it toward another notch, V, the hole iu the bar M being then above said notch V. This motion ofthe lever causes the shaft G to be swung, so as to throw it oit' the shaft I, while the belt 'i is stretched. The motion of the carriage is thereby reversed.

lheu the pin 1), striking o, moves the bar M, so as to lit the wedge 'r under the lever, the latter will he lifted out of the notch V, and moved by the weight again into the notch u, the hole in M being then above4 said notch n. Thus the movementof the carriage is automatically reversed, andA can be made faster or slower for forward or return'moves, by varying the diameters of the respective pulleys and friction-wheels.

By setting the piu O nearer to or further from the wedge s, the stroke of the carriage can be regulated for shorter 'or longer logs. The log on the head-block is moved by means of a shaft,N, hung in the carriage H. The shaft N receives intermittent rotary motion by" means of a weighted pawl, I?, engaging the teeth ofa ratchet-wheel, t, which is mounted' upon the shaft N. The pawl P, or set of pawls, if desired, is pivoted to an L-shaped bar, It, pivoted loosely to the end of the shaft N. The long arm of the bar R is weighted and carries at its end a transverse socket in which a sliding pill, rt, is held, the same being thrown out by a spring concealed within the said socket. This pin o; rests during the motion of the carriage ou ahorizon tal track y of the frame A until it strikes a wedge, .7, fixed to the end of said trac-k.

This wedge pushes the pin :1: luto the socket and causes thereby the bar Rv to drop, which movement turns the shaftN for setting the loir.

During the return stroke the socket is gradually raised on `an incline, S, until it again is in line with the track y, when the pin a: will spring out to support it. By having a double incline, S, as inv fig. 4, and a` economical than heretofore. However, by leaving outl one of the wedges, the setting of the log during the return stroke can be dispensed with. By bringing the wedges nearer together or further apart, the aymaratus is adjusted for shorter or longer logs.

. YIt will be seen that this machine is of simple construction and very effective in its operation, besides being adjustable in every degree to all lengths of logs and manner of sawing. It can be rigged up for portable or stationary mills, and can bc readily pnt up' wherever desired.

A gang of saws may, if desired, he mounted upon the shaft E, whenever the machine is to be used for single action only, i. c., when cutting during backward motion of the carriage is not required. A slotted, vertically-adjustable stop, I1', may be used on the carriage for regulating the amount of' motion that is each time imparted to the shaft N by the falling of' the bar R.

Having thus described my invention,

I elaim as new and desire to secure by Letters Patenty' 1. The piroted lever L, united with the slide h, that holds the adjustable shaft G, and combined with the weight m and slide M, substantially as herein shown and described, to operate as set forth.

2. 'lhe slide M, provided with a pin, 0,'to be set by the log-carriage, and with the wedges fr' and s, for releasing the lever L from the not-ches v and 1l, substantially as herein shown and described.

3. The weighted pawl-lever It, combined ,with the spring-pin af, track a, and wedge or wedges z, to operate the head-block, substantially as herein shown and described.

4 The adjustable stop b', applied t'o the carriage H, in combination with the pawl-lever R, substan- 'tially as and for the purpose herein shown and described.

XVitnesses: FRED. T. STEV MELVLN MARSHALL, CLARK STEVENS. 

